Forty-nine-year-old Elaine Herzberg was struck and killed by an Uber-modified Volvo XC90 while she was attempting to cross the road at night, and a video later revealed the car’s human minder was looking down at the time of the crash.

“I found the video (of the crash) to be disturbing and alarming, and it raises many questions about the ability of Uber to continue testing in Arizona,” Ducey wrote to Uber CEO Dara Khosrowshahi. Noting the crash was an “unquestionable failure to comply” with the expectation that public safety be the top priority for self-driving car tests, Ducey directed the state’s Dept. of Transportation to suspend Uber’s testing on public roadways.

“Arizona will not tolerate anything less than an unequivocal commitment to public safety,” Ducey wrote.

The governor’s order comes after numerous questions were raised about the safety of Uber’s test cars. As Jalopnik reported, the company recently switched to only using one human minder instead of two, as is the typical industry standard. Additionally Uber’s cars were revealed to require far more “interventions” by human minders than similar cars made by Google’s Waymo and others.

The announcement tonight also represents a big change for Arizona, which under Ducey initially welcomed a great deal of self-driving car testing by various companies—many of whom arrived from California after that state sought to enforce stricter safety regulations.

Not anymore, that’s for sure.